Clothes drier with vapor removal



Filed Dec. 5, 1960 June 22, 1965 s. s. SHIELDS 3,190,011 CLOTHES DRIER WITH VAPOR REMOVAL 2 Sheets-Sheet l INVENTOR.

A rrqezvsys June 22, 1965 s. s. SHIELDS CLOTHES DRIER WITH VAPOR REMOVAL 2 Sheets-Sheet 2 Filed Dec. 5, 1960 INVENTOR. $56OUG'H 6. 57176406 s top and to one side of the chamber.

United States Patent 3,199,011 CLOTHES DRIER WITH VAPGR REMUVAL Sebeugh S. Shields, Cleveland Heights, Ohio, assignor to Nouhar S. Abdalian, South Euclid, and Robert V. Ahdalian, Cleveland Heights, Qhio Filed Dec. 5, was, Ser. No. 7 3,609 Claims. 6C1. 34-77) This invention pertains to clothes driers and more particularly to that class of clothes driers which are utilized in the dry cleaning industry.

In the dry cleaning industry, clothes are often cleaned with solvents which are very oifensive to the human sense of smell. Further, many of these solvents are quite toxic. They are also rather expensive, especially when purchased and used in the quantities required in the dry cleaning industry.

A drier must remove all, or at least substantially all, solvents from clothing or other articles which have been cleaned. It is preferable that all trace of odor be carried from these articles. The drier takes these solvents from the articles in vapor form and it should condense and reclaim substantially all of these vapors for the combined purpose of the economy of reusing the solvent and of avoiding oifensive and perhaps toxic odors in the vicinity of the drier.

inherently, it is also important that a commercial clothes drier be simple, rugged, inexpensive and efficient. It is important that the drier remove all solvents from articles as quickly as possible to permit maximum utilization of the drier.

All of these listed and other factors contribute to requirements for a good drier for the dry cleaning industry. With previously known driers, articles carried in the tumbler tend to mat together and move together maintaining essentially the same relative position. These articles, when matted, move with the tumbler as it rotates, until that portion of the tumbler which they abut becomes substantially the top portion of the tumler. The matted articles will then drop away more or less as a unit and the cycle will be repeated. Thus, articles positioned in a rotating tumbler will tend to transcribe a generally elliptical or oval path while maintaining a generally constant relative position.

It has been discovered that through proper control of the flow of air through the drying chamber, the articles can be caused to be separated from one another and from the walls of the tumbler. This action opens the articles up and exposes them to greatly increased quantities of air flowing through the drying chamber thereby producing highly superior drying results. These results are obtained in the preferred and disclosed arrangement by bringing heated air under pressure into the drying chamber at the This inflow of air at the top tends to blow any clothes or articles clinging to the walls of the tumbler away from those walls.

Air is then drawn olr through two outlets on the opposite side of the chamber. The outlets are spaced from one another with one below the tumbler and one above the horizontal center line of the tunibuer but spaced downwardly somewhat from the top of the drying chamber. These two outlets tend to produce a vacuous area along the side of the chamber where the clothes are rising with the tumbler and which causes the clothes to drop away from the walls of the tumbler. The overall result is a thorough mixing and loosening action of the articles being dried.

Another discovery which has led to improved results in a commercial drier is a provision of a small outlet opening from a condensing cavity where solvents carried by the drying air are condensed. This small outlet opening causes the air to be compressed in the condensing cavity.

The air is also cooled in that cavity for the purpose of condensing the majority of solvent out of the air. The compressed air passes through the small condensing cavity outlet into a relatively large expansion cavity. The sudden release of pressure as the air passes into the expansion cavity causes a cooling. The outlet of the expansion cavity is at the top while the inlet from the condensing cavity is at the bottom. The sudden cooling coupled with the rising of the air as it passes to the expansion cavity outlet, causes any entrained solvents to both condense and drop out of the air. This dried air is then passed into a heating cavity and then back into the drying chamber.

Another feature of the invention is a novel venting arrangement which must be opened before the access door to the drying chamber can be opened. With this arrangement a bame which selectively closes a venting outlet pipe and another baiiie which selectively closes an air inlet to the drying chamber, both must be opened before the door can be opened. One of these battles, when in the opened position, closes the communication between the blower or fan cavity and the condensing cavity. When the access door is open, fresh air is drawn in throgh the door opening as well as the venting inlet protecting the operator from exposure to toxic or offensive fumes.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a sectional view of the novel and improved commercial clothes drier with the bafiles in the closed position and showing the flow of air during a drying cycle;

FIGURE 2 is a fragmentary sectional view of the top of the drier showing the battles in their second position and the path of air when the drying chamber is being vented; and,

FIGURE 3 is a perspective view with parts of the drier being shown in phantom showing the interlock arrangement which prevents the opening of the door when the handles are in the closed position.

Referring now to the drawings and to FIGURE 1 in particular, a housing is shown generally at 10. The housing 10 includes a base support portion or pedestal 11. The housing It) defines a drying chamber 12. A tumbler i3 is disposed within the drying chamber. The tumbler 13) is journaled at 14 for rotation to tumble articles disposed in the drier when those articles are being dried.

The tumbler 13 includes a cylindrically contoured peripheral wall 15. The peripheral wall 15 is perforated to facilitate the passage of drying air into and out of the tumbler 13. A tumbler access door 17 closes a suitable aperture through which clothing and other articles can be passed for insertion and removal from the tumbler 13.

The housing 10 includes a drying chamber top wall 18. The chamber top wall 18 defines the top of the chamber 12. The chamber top wall includes an air inlet passage 19 and an air outlet passage 29. An air conducting and treating conduit is shown generally at 22;. The air conducting and treating conduit defines a tortuous air treatment path connecting the outlet 2b with the inlet 19.

The air conduction and treatment conduit includes walls 23 which define a compression cavity 24. The conduit 22 also includes walls 25 which define an air conduction conduit 26. The air conduction conduit 26 connects the chamber top wall outlet 20 with the compression chamber 24. A blower 28 is positioned in the compression chamber 24. The blower 28 is driven by a motor 29 which is mounted on the top 30 of the drier housing 10.

The air conduction and treatment conduit 22 has a condensing cavity 31 adjacent the compression cavity 24. A partition wall 32 separates the compression cavity 24 and the condensing cavity 31. The partition wall 32 has a 3 connecting aperture 33 to provide an outlet for the compression cavity and an inlet for the condensing cavity.

Cooling coils 34 are disposed in the condensing cavity to cool and thereby condense vapors entrained in air passing through the condensing cavity 31. The condensed vapors drop onto a canted condensing base wall 35 which serves as a drop or collection tray for the condensing cavity. The air conduction and treatment conduit has an expansion cavity as adjacent the condensing cavity 31. The canted base wall 35 extends into and forms substantially all of the bottom of the expansion cavity 3-3.

A partition wall 37 separates the compression cavity 31 from the expansion cavity 36. The partition wall 37 extends from the top downwardly. The partition wall 37 terminates a short space from the canted bottom wall to define an opening 38. The opening 38 is the outlet for the condensing chamber 31 and the inlet for the expansion cavity 36.

The opening 3% provides one of the outstanding advantages of the invention. The opening 38 is of a cross sectional area which is substantially less than the cross sectional area of the condensing cavity inlet 33. Since the cavity outlet 38 is substantially smaller than the inlet 33,

air and entrained vapors are actually compressed in the condensing cavity 31. Thus, the air is both cooled and compressed in the condensing cavity 31. As compressed air passes through the opening 36 and into the expansion cavity 36, it expands very rapidly and a further cooling takes place. This expansion and cooling causes any still entrained vapors to condense. A partition wall 41 ex tends upwardly from the base of the expansion cavity 36 and terminates short of the top 30 to define the expansion cavity outlet 49. Air passes from the opening 3% through the expansion cavity and out the outlet 49. As the air passes through the expansion cavity the vapors which condense in the expansion cavity 36 drop out of the moving air as it advances to an expansion cavity outlet 40. g

The .wall 41 and a flat base 42 together with the lower edge of the canted base wall $5 define a collection trap for the condensed solvents. The condensed solvents are then passed through an outlet aperture 43 into a return pipe 44 which delivers the condensed solvents to a collection tank, not shown.

The final cavity of the air conduction and treatment conduit 22 is a heating cavity 45. The heating cavity 45 includes heating coils 46 which warm the air prior to its delivery from the heating cavity 45 through the top wall inlet 19.

A first interior bafile 4% defines one side of the drying chamber 12. The bafile $8 is spaced inwardly from housing side wall 49 to define an air conduction conduit 50 at the right hand side of the drier as seen in the drawings. The baffle 43 has a drying chamber main outlet aperture 51 formed in it. The main outlet aperture 51 is at the base of the drying chamber 12. The drying main outlet aperture is also at the base of the conduit 5t and serves as an inlet to the conduit. Air passes from the drying chamber 12 through the main outlet aperture 51,

, through the conduit 50, through a connecting aperture 52 w and then through the top wall outlet aperture 20.

A supplemental bai'lle 55 extends downwardly from the chamber top wall to define a part of the peripheral extremity of the drying chamber 12. The supplemental bafiie 55 has a lower edge 56 which is spaced from the plane passing through the axis of tumbler rotation. The

top wall inlet 19, on the other hand, is positioned to the a left of this plane and adjacent opposite side wall 57 of the housing 10.

A removable lint filter 53 is positioned across the main outlet aperture 51. The removable lint filter 53 is accessible through a trap door, not shown, in the front wall of the housing 19. A second removable lint filter 54 is positioned across the top wall outlet 2 and removable in a similar fashion.

The relative positioning of the inlet 19 and the outlets 51, 5% provides one of the outstanding advantages of the invention. Since most of the circulating air is drawn out through the main outlet aperture 51 and the remaining circulating air is drawn out through the supplemental outlet aperture 53, the region along one side of the chamber 12, again the right as seen in the drawings, has a reduced pressure. This region, in fact, becomes a vacuous region. Since this pressure is reduced at the base of the chamber, and further reduced at a location near but spaced from the chamber top wall 18, articles carried in the rotating tumbler 13 tend to drop away from the wall 15 of the tumbler as they rise up the right side while the tumbler rotates counterclockwise. Any articles which may tend to cling across the top of the chamber are blown free by the incoming air coming through the inlet opening 19. Further, this inrushing air strikes the loosened articles as they drop away from the wall 15 and thoroughly agitates and mixes those articles.

These described reasons are believed to be the explanation for the outstanding tumbling action which is achieved with this construction and which results in reduced drying time. A discovery that substantiates the described reasons is that if the supplemental baffle 55 is eliminated and the top Wall outlet 20 serves as the supplemental outlet, the tumbling action, though better than in prior mechanisms, is not as effective as in the disclosed construction.

Thus, the provision of the main outlet at the base of the tumbler provides the greatest advantage over the art and the additional provision of a supplemental outlet in the upper half of the chamber 12 but spaced downwardly from the top Wall 18 greatly enhances the overall efliciency.

Other features of the invention are best seen in FIG- URES 2 and 3. A fresh air inlet vent 60 is formed in the wall 57 and communicates with the drying chamber 12. An outlet vent 61 is in communication with the compression chamber 24, through the top 39. An inlet bafile 62 is positionable across the fresh air inlet vent 61, and an outlet bafiie 63 is positionable across the outlet vent 61. The baffles 62, 63 is across the vent to close it, as seen in FIGURE 1, during the drying operation.

Prior to opening the access door 17, the baffles 62, 63 are shifted to the position shown in FIGURE 2 to open the inlet and outlet vents 60, 61, respectively. The baffie 63 also has the function of closing the aperture 33 which forms the communication between the compression cavity 24 and condensing cavity 31.

The baffies 62, 63 are simultaneously shifted from their closed to their open positions, or return, through a linkage controlled by a control handle 65. Rotation of the handle 65 causes a shaft 66 to rotate. shaft 66 drives chain 67 which in turn actuates linkage 68 which controls the outlet bafiie 63. Rotation of the shaft 66 also actuates an eccentric 69 which controls a linkage 70 connected to the inlet bafile 62. Another eccentric 71 actuates a vent door lock bar 72 to engage or disengage a tab '73. The tab 73 is secured to and forms a part of the door 17. Thus, when the venting linkage is in the closed position of FIGURE 3 the lock bar 72 locks the door 17 in a closed position. When the vents are shifted to their open positions, the lock bar 72 disengages the tab 73 thereby unlocking the door. Hence, the vents must be open permitting the blower to cause fresh air to Rotation of the cause when the door 17 is opened fresh air is drawn in through the access door. Since air is drawn in the door aperture, vapors do not escape through the aperture.

While the invention has been described with a great deal of detail, it is believed that it is essentially comprised of a clothes drier with a novel and improved air fiow and treatment pattern including an improved flow through the drying chamber and an improved drying and treatment of the air in an air conduction and treatment conduit. The invention also provides an improved and safe air flow pattern when an access door is open.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed:

1. In a clothes drier having a housing defining a drying chamber and a tumbler journaled in the chamber for rotation therein, the combination of, a chamber inlet opening and a spaced pair of chamber outlet openings in the housing, air conducting conduit means connecting the chamber outlets to the chamber inlet, a blower disposed in said conduit means, said conduit means also including a condensing cavity, an expansion cavity, and a heating cavity, said condensing cavity having an inlet and an outlet of substantially smaller cross section, said condensing cavity outlet being the expansion cavity inlet, said expansion cavity having a greater cross section than the condensing cavity outlet, the expansion cavity outlet being the heating chamber inlet, said expansion cavity having a condensed solvent trap positioned between its inlet and outlet openings to prevent the condensed solvent passing into the heating cavity, and one of said chamber outlets being above and the other below a horizontal plane passing through the axis of the tumbler rotation.

2. A clothes drier comprising a housing defining a drying chamber, a tumbler journaled in the chamber for rotation therein, said housing including a wall defining the top of said chamber, said wall having an air inlet opening and an air outlet opening, a first baifie disposed within the housing between the tumbler and one side wall of the housing, the first batfie being spaced from said one side wall and secured to the housing to define an air conducting conduit between the first bafile and the one side Wall, said first bafiie at least in part defining a chamber outlet opening below the tumbler and a conduit outlet opening adjacent the top wall air outlet, a second baflle disposed within the housing and defining at least a portion of a second chamber outlet opening, said second bafi le being secured to the housing and said bafiies and housing together defining a second air conduction conduit connecting said second chamber outlet opening to said top wall air outlet, a blower secured to the housing and mounted above said top wall outlet, said housing including walls defining a condensing cavity having an inlet opening, said condensing cavity having an outlet opening of smaller cross-sectional area than the condenser cavity inlet opening, said housing also including walls defining an air conducting cavity connecting the top wall outlet opening with the condenser chamber inlet, said blower being disposed in said conducting cavity, said housing also including walls defining an expansion cavity with a top outlet opening and in communication with the condensing cavity outlet opening, and said walls defining a heating cavity connecting the expansion cavity to the top wall inlet.

3. The device of claim 2 wherein said housing walls include a canted lower wall defining the bottom of said condensing cavity and said expansion cavity, and wherein a solvent collection trap is at the base of said canted wall.

4. The device of claim 3 wherein said condensing cavity outlet opening is adjacent said canted Wall.

5. The device of claim 2 wherein a removable lint filter is positioned across said first chamber outlet opening and a second removable lint filter is positioned across said top wall outlet.

6. The device of claim 2 wherein said housing has a clothes insertion and removal aperture, a door selectively closing said aperture, an outlet vent communicating with said air conducting cavity, an inlet vent communicating with said chamber, first and second bafile means movably mounted to selectively close said inlet and outlet vents respectively, and interlock means preventing the opening of said door when said bathe means are in the closed position.

'7. In a drier having a housing defining a drying chamber, the housing having an inlet opening for directing air into the drying chamber and an outlet opening for drawing moisture laden air out of the drying chamber, the combination of a closed air circulating and treatment system for removing a maximum quantity of cleaning fiuid from moisture laden air drawn from the drying chamber, said combination comprising; an air conducting conduit connecting the outlet opening to the inlet opening, said air conduit including an air treatment chamber portion, said air treatment chamber portion including wall members defining a condensing cavity and a condensing cavity inlet connected to the drying chamber outlet opening, a first partition secured to said wall members and defining a condensing cavity outlet therewith, said condenser cavity outlet having a smaller cross-section than said condenser cavity inlet, a second partition secured to said wall members in spaced, substantially parallel relation to said first partition, said first and second partitions defining an expansion cavity therebetween having an axial air fiow substantially at right angles to that through the condenser cavity outlet, said second partition and said wall members defining a heating cavity inlet, and said wall members defining a heating cavity and a heating cavity outlet connected to the drying chamber inlet opening.

8. In a drier having a housing defining a drying cham her, the housing having an inlet opening for directing air into the drying chamber and an outlet opening for drawing moisture laden air out or" the drying chamber, the combination of a closed air circulating and treatment system for removing a maximum quantity of cleaning fluid from moisture laden air drawn from the drying chamber, said combination comprising; an air conducting conduit connecting the outlet opening to the inlet opening, said air conduit including an air treatment chamber portion, said air treatment chamber including wall members defining a condensing cavity and a condensing cavity inlet connected to the drying chamber outlet opening, a partition means secured to said wall members and defining a condensing cavity outlet therewith, said condenser cavity outlet having a smaller cross-section than said condenser cavity inlet, said partition means and said Wall members defining an expansion cavity having a canted bottom surface, the inlet of said expansion cavity being the condensing cavity outlet, said canted bottom surface including a collection trap for collecting condensed cleaning fluid, said Wall members defining a heating cavity inlet at the downstream end of said expansion cavity, said wall members defining a heating cavity and a heating cavity outlet connected to said drying chamber inlet, and said canted bottom surface and said collection trap being positioned in said expansion cavity to drain the condensed cleaning liquid away from said heating cavity inlet.

9. In a drier having a housing defining a drying chamber, the housing having an inlet opening for directing air into the drying chamber and an outlet opening for drawing moisture laden air out of the drying chamber, the combination of a closed air circulating and treatment system for removing a maximum quantity of cleaning fluid from moisture laden air drawn from the drying chamber, said combination comprising:

(a) wall means including upper and lower wall memoers defining an air conducting conduit connecting the outlet opening to the inlet opening, portions of said conduit defining an air treatment chamber;

(b) a first partition connected to said wall means between said openings and extending from said upper Wall member toward said lower wall member, said first partition defining a restricted air opening adja- 7 cent said lower wall member;

() a second partition connected to said wall means spaced from said first partition and extending from said lower wall member toward said upper wall member, said second partition including portions defining an air opening adjacent said upper wall member;

(d) the space between said partitions comprising an errpansion cavity within said air treatment chamber;

(e) at least part of the air treatment chamber between said inlet opening and said first partition comprising a condensing cavity; and

(f) at least part of the air treatment chamber between said outlet opening and said second partition comprising a heating cavity.

310. A clothes drier having a housing defining a drying chamber, a tumbler journaled in the chamber for rotation therein, the tumbler having perforate regions for the admission and exit of a drying fluid into and from an internal clothes receiving chamber defined by the tumbler, the housing including a chamber inlet opening for directing the flow of drying fluid through the perforate regions of 'the tumbler into the clothes chamber defined by the tumbler, said housing having a pair of chamber outlet openings for withdrawing the drying fluid through perforate regions of the tumbler, a fluid treating conduit means connecting the chamber outlets to the chamber inlet, said conduit means including a condensing cavity, a heating cavity and a blower disposed in the conduit means for causing the circulation of drying fluid from the conduit means into the clothes chamber and from the clothes chamber back into the conduit means, and said chamber outlets being relatively spaced one above and the other below a horizontal plane passing through the axis of the tumbler rotation so as 'to withdraw the drying fluid through two spaced difierent perforate regions of the tumbler and separate the fiuid flowing in the clothes chamber into a first fiuid flow traversing primarily the upper space of the clothes chamber and a second fluid flow traversing primarily the lower space of the clothes chamber.

11. The device of claim wherein said one chamber outlet is below the tumbler, and said other chamber out et is below and spaced from the top of the chamber.

12. The deviceof claim 16} wherein the chamber inlet is at the top of the chamber and at one side of an imaginary vertical plane passing through the center of said chamber and wherein the chamber outlets are at the other side of such plane.

13. In a clothes drier having a housing defining a drying chamber and a cylindrical tumbler disposed within the chamber and journaled therein for rotation in a predetermined angular direction relative thereto, the improvement for thoroughly separating the articles being dried in the tumbler and to expose these articles to maximum quantities of drying air flowing through the drying chamber, said improvement comprising; a chamber inlet opening in the housing to direct the drying air into the tumbler, said chamber inlet opening being adjacent to a cylindrical surface of the tumbler and positioned to direct the fiow of air through perforations in the said cylindrical surface against the rotation of articles within the tumbler, a spaced pair of chamber out et openings in the housing to remove moisture laden drying air from the tumbler, an air conducting conduit connecting said outlet openings to said inlet opening exteriorly of said tumbler and-of said drying chamber, a blower connected to said air conduit to cause drying air to flow into said drying chamber through said inlet opening and out of said drying chamber through said outlet openings, one of said outlet openings being located above an imaginary horizontal plane passing through the axis of tumbler rotation and on the opposite side of an imaginary vertical plane passing through the aids of tumbler rotation from said inlet opening, and the other of said outlet openings being located clow said horizontal plane and on the opposite side of said vertical plane from said inlet opening, whereby the drying air is withdrawn through two spaced different per- :"orate regions of the tumbler and is at least partially se arated in the tumbler into a first air fiow traversing primarily the upper space within the tumbler and a second air flow traversing primarily the lower space Within the tumbler.

14-. The combination of claim 13 wherein the outlet opening located above said horizontal plane has a smaller cross-sectional area than the other or" said outlet openin s so that a greater portion of the drying air is withdrawn from the tumbler through the outlet opening below the horizontal plane.

l5.A clothes drier comprising a housing defining a drying chamber, a perforated tumbler journaled in the chamber for rotation therein, said housing including a top wall defining the top of said chamber and side walls defining opposite sides of said chambers, said top Wall having an air outlet opening located adjacent one side wall and an air inlet opening located adjacent the opposite side wall, a first battle disposed Within the housing between the tumbler and said one side wall of the housing, the first bafile being spaced from said one side wall and secured to the housing to define an air conducting conduit between the first baffle and the one side Wall, said first bafiie at least in part defining a chamber outlet opening below the tumbler and a conduit outlet opening adjacent the top wall air outlet, a second bafiie disposed within the housing and defining at least a portion of a second chamber outlet opening located below the top wall and above the axis of tumbler rotation, said second bafile being secured to the housing and said battles and housing together defining a second air conduction conduit connecting said second chamber outlet opening 'to said top Wall air outlet, an air treatment chamber connecting said air outlet opening to said air inlet opening, and a blower disposed in said treatment chamber for directing drying air through said air inlet opening into said drying chamber and for withdrawing air from different regions of the drying chamber through first said chamber outlets, then into said treatment chamber through said air outlet opening.

References ited by the Examiner:

UNITED STATES PATENTS NORMAN YUDKOFF, Primary Exalm'ner.

BENJAMIN BENDETT, Examiner. 

1. IN A CLOTHES DRIER HAVING A HOUSING DEFINING A DRYING CHAMBER AND A TUMBLER JOURNALED IN THE CHAMBER FOR ROTATION THEREIN, THE COMBINATION OF, A CHAMBER INLET OPENING AND A SPACED PAIR OF CHAMBER OUTLET OPENINGS IN THE HOUSING, AIR CONDUCTING CONDUIT MEANS CONNECTING THE CHAMBER OUTLETS TO THE CHAMBER INLET, A BLOWER DISPOSED IN SAID CONDUIT MEANS, SAID CONDUIT MEANS ALSO INCLUDING A CONDENSING CAVITY, AN EXPANSION CAVITY, AND A HEATING CAVITY, SAID CONDENSING CAVITY HAVING AN INLET AND AN OUTLET OF SUBSTANTIALLY SMALLER CROSS SECTION, SAID CONDENSING CAVITY OUTLET BEING THE EXPANSION CAVITY INLET, SAID EXPANSION CAVITY HAVING A GREATER CROSS SECTION THAN THE CONDENSING CAVITY OUTLET, THE EXPANSION CAVITY OUTLET BEING THE HEATING CHAMBER INLET, SAID EXPANSION CAVITY HAVING A CONDENSED SOLVENT TRAP POSITIONED BETWEEN ITS INLET AND OUTLET OPENINGS TO PREVENT THE CONDENSED SOLVENT PASSING INTO THE HEATING CAVITY, AND ONE OF SAID CHAMBER OUT- 